| 摘要 |
PROBLEM TO BE SOLVED: To enable a more suitable correction of thermal displacement over the full length of a workpiece by neither increasing the number of temperature sensors installed in a machine, nor generating diameter differences or streaks in a workpiece even when the spindle is switched at any position of a workpiece center with regard to means of correcting a position command for a tool in a processing area formed on each spindle side of a two-spindle counter lathe.SOLUTION: A correction value of thermal displacement at the center of a workpiece length is calculated according to a position in a spindle axis direction of a tool. A correction value of right and left spindles is arithmetically operated, and an obtained arithmetic value is interpolated according to a position in the spindle axis direction of a tool with respect to an interspindle distance. For each processing area on each spindle side, a controller 10 registers correction arithmetic expressions 15a, 15b including variables of detected temperatures of a plurality of temperature sensors installed in a machine 1 to use a correction value to which two arithmetic values obtained by the correction arithmetic expressions 15a, 15b have been interpolated with a relative position of the workpiece and the tool in the spindle axis direction.SELECTED DRAWING: Figure 2 |
